The studs may have just broke and the mud got on them which causes rapid corrosion of raw metal. He said it happened right as he went in a mud hole. I would say, judging from the rim galling, that your lug nuts were loose to start with which would put alot of angular pressure on the studs whereas on tight wouldn't. Other cause could have been overtightening. Either way that sucks. A guy I rode with before Christmas had problems with his lugnuts coming off. But he was complaining about the dealer not doing it right, come to find out, he bought the Rubicon, and put the wheels on himself, operator error. But I would say the studs didn't "just break" something else must have happened from either not tight enough or too tight, because I zip mine on with an 1/2" impact every time I ride and clean my Foreman up. I do use antiseize everytime too though.
